Gulab jamuns (assumed to be spherical) are to be heated in on oven They are available in two sizes, one twice bigger (in radius) than the other Pizzas (assumed to discs) are also to be heated ibn oven They are also in two sizes, one twice bigger (in radius) than the other All four are put together to be heated option to oven temperature. Choose the correct option from the following .

Options

A. Both size gulab jamuns will get heated in the same time
B. Smaller gulab jamuns are heated before bigger ones
C. Smaller pizzas are heated before bigger ones
D. Bigger pizzas are heated before smaller

Explanation

To solve the problem regarding the heating of gulab jamuns and pizzas of different sizes, we need to analyze the relationship between their sizes, specifically their surface areas, and how that affects their heating.

### Step-by-Step Solution:

1. **Understand the Shapes and Sizes**:
- Gulab jamuns are spherical.
- Pizzas are circular discs.
- There are two sizes for each: one with a radius \( r \) and another with a radius \( 2r \).

2. **Calculate Surface Area**:
- For a sphere (gulab jamun), the surface area \( A \) is given by the formula:
\[ A = 4\pi r^2 \]
- For a disc (pizza), the surface area \( A \) is given by the formula:
\[ A = \pi r^2 \]

3. **Surface Area Comparison**:
- For the smaller gulab jamun (radius \( r \)):
\[ A_{\text{small gulab}} = 4\pi r^2 \]
- For the larger gulab jamun (radius \( 2r \)):
\[ A_{\text{large gulab}} = 4\pi (2r)^2 = 16\pi r^2 \]
- For the smaller pizza (radius \( r \)):
\[ A_{\text{small pizza}} = \pi r^2 \]
- For the larger pizza (radius \( 2r \)):
\[ A_{\text{large pizza}} = \pi (2r)^2 = 4\pi r^2 \]

4. **Analyze Heating**:
- The rate of heating is inversely related to the surface area. A smaller surface area means that the object will heat up faster.
- Comparing the surface areas:
- Smaller gulab jamun has a surface area of \( 4\pi r^2 \) (smallest).
- Larger gulab jamun has a surface area of \( 16\pi r^2 \) (largest).
- Smaller pizza has a surface area of \( \pi r^2 \) (smallest).
- Larger pizza has a surface area of \( 4\pi r^2 \) (larger than the smaller pizza but smaller than the larger gulab jamun).

5. **Conclusion**:
- Smaller gulab jamuns will heat up before the larger gulab jamuns due to having the least surface area.
- Smaller pizzas will heat up before the larger pizzas for the same reason.
- Therefore, the correct options are:
- Smaller gulab jamuns are heated before the bigger ones.
- Smaller pizzas are heated before the bigger ones.